The sky is a challenging place to live, but extraordinary animals do something we only dream of-take to the air. Some spend their lives airborne, others only visit-but they all have one thing in common; they only survive by taking to the skies. This three part series reveals the incredible adaptations that explain how these animals have mastered the sky and why they all need it to survive.

This documentary really explains a lot about how flight takes affect.Understanding birds (I'm a birder) really explains how they get their energy and power for their travel. Many other animals are really explained!

Tuned into last ~30 minutes of "Crowded Skies" yesterday. Was mesmerized by the content -- could not take my eyes off the program. Now, am buying the series to watch in its entirety. Highly recommend because we've watched many nature programs but this series has AMAZING footage we've never before seen and facts never before knew.

What a fantastic nature program, especially the part that had to be constructed to film the Flying Snake(defying gravity, Episode 2). Outstanding. Congrats to crew and everyone involved to produce this show.

When you combine the creative investigation skill of humans with the creative skills of nature on earth you get a result that surpasses imagination...everyone should see this just to get some perspective about life on planet earth.